The present invention relates to the improvement of a waterproof connector that is covered by a grommet and fixed by a bolt to a corresponding housing.
One example of this type of waterproof connector is a connector attached to a panel, as described in JP 6-72177. As shown in FIG. 5 of this specification, this waterproof connector has a male housing 2 attached, in a waiting state, to a panel 1 via an attachment hole 1A of this panel 1. A waterproof female housing 3 is fitted to this male housing 2. A posterior face of the female housing 3 is covered by a grommet 4 which makes contact with hole edges of the attachment hole 1A, thereby sealing the attachment hole 1A. Furthermore, the grommet 4 is provided with a tubular member 4A that leads a bundle of electric wires in a specified direction. The grommet 4 is passed through the female housing 3, then a bolt 5 is attached thereto. A nut 6 attached to the male housing 2 is screwed to the bolt 5, thus fastening the two housings 2 and 3 together.
In this type of connector, if the electric wires that have been led outwards have a pulling force exerted thereon such that the tubular member 4A changes shape in either of the directions shown by the arrows in FIG. 5, this change of shape may affect an inserted portion 7 of the bolt 5, (i.e., the portion of the bolt 5 passing through the grommet 4). A space may appear between the grommet 4 and the inserted portion 7, thus damaging the seal around the bolt 5. Conventionally, this problem has been dealt with by covering the exterior of the grommet 4 with a rigid plastic cover 8, this pushing down on the grommet 4 since the two are fastened together. This cover 8 prevents the inserted portion 7 etc. of the bolt 5 from changing shape as a result of the grommet 4 changing shape.
Since the conventional connector requires an extra component, namely, the cover 8, the number of components increases, and production costs increase commensurately. The present invention has taken the above problem into consideration, and aims to present a waterproof connector in which the seal is maintained around the bolt without having to increase the number of components.
According to the invention there is provided a waterproof connector comprising a first housing engageable with a second housing, and a screw-threaded bolt operable between the housings to fasten the housings together, one of said housings having a resilient waterproofing cover, and an aperture in the cover to resiliently receive the shaft of said bolt, characterized in that said cover includes a tubular portion to receive said shaft, at least part of said tubular portion being housed in a corresponding recess of said one of said housings, and in use said cover being gripped between the head of said bolt and said one of said housings.
Such an arrangement ensures that the tubular portion of the cover grips the shaft of the bolt despite movement of wires which exit from the cover.
Preferably a recess is provided on the inside surface of the cover and for engagement with a tubular bolt receiving projection of the housing. Such an arrangement enhances sealing.
Preferably the projection engages closely with the rim defining this recess, and in the preferred embodiment the projection has an edge for engaging the inside surface of the cover. This edge is preferable triangular in section and engages with a recess of mating form. In the preferred embodiment the recess and projection are circular and concentric.